Well pipe plug



G. S. KNOX WELL PIPE PLUG Filed June 26, 1937 Jung 25, 1940.

2 Slaeets-,Sheeil l Inventor. Era/1m lle LS. N11/aac.

Mgg

June 25, 1940. G, s KNOX 2,205,748

WELL PIPE PLUG Patented June 25, 1940 UNITED STATES PATENT OFFICE WELL PIPE PLUG to Hydril Company,

Application June 2s, 1937, semi No. 150,569`vr 13 Claims.

This invention pertains generally to well pipe plugs, particularly casing plugs, adapted to be operated and controlled by way of the suspension means on which the plug is lowered in the well. This type of plug is distinguished by its general mode of operation from pump-down plugs, which are forced down ahead of a fluid column and which ordinarily set, independently of any direct actuation from the ground surw face, when some predetermined condition is established. The invention may befurther characterized as involving, in some of its aspects, improvements on the invention disclosed in United States Letters Patent No. 1,971,514,

15 granted August 28, 1934, to Frederick Stone on Casing plug. v

In its preferred form; the invention has in common with the type of plug shown in the Stone patent, three principal operatingparts:

radially expansible means adapted to be brought into holding engagement with the pipe or casing,

a radially expansible packer, and a valve adapted to open or close a fluid passage extending through the plug from one side to the other of the packer. And also, as in `the patented plug,

these principal operating partsv preferably are positively actuated and controlled by way of the suspension means which, ordinarily, will consist of a string of drill pipe. One of my principal objects is to cause and insure the operation of the plug parts in a novel predetermined sequence without consciouseifort on thepart of the operator to maintain that sequence,. and thereby to obviate many of the difliculties comm monly encountered in the use of such plugs.

In lowering the plug, the valve ordinarily is kept open to by-pass well uid through the plug and thereby avoids yhaving to force down the plug against the hydrostatic head of liquid in 40' the well. In accordance with the operating sequence aspect of the invention, the plug setting operation involves, and requires, rst, closing the valve, and/then expanding the holding means and. packer, preferably though not necessarily 43 in the order` named, into engagement with the` `casing. To release the plug from set condition itis necessary rst to open the valve, and then to contract the packer and holding means. The :required initial opening of the valve is of im- 50 portan'ce inv that sometimes an operator will attempt to release a plug without first relieving the pressure beneath the plug, with the result that either the plug cannot be released because of the applied pressure, or a forced release will re- 5 suit in breaking some of its parts.

(Cl. 16B-13) A further feature ofrthe inventiomand onev which is believed to be a broadly novel improve-` ment, is the provision of means whereby any or all of the operating parts mentioned above may repeatedly be actuated, i. e., the valve repeatedly '5 opened and closed, and the pipe engaging means and packer repeatedly expanded and contracted, while the plug is lowered in the casing and while it remains connected to the suspension means.

By this means the plug may be set andreset at l0 di'erent locations and as many times as may be necessary without having to withdraw the plug or suspension means, or, leaving the plug in the casing, the suspension means may be run in and out of the casing any number of times to l5 reset and change the position of the plug;

Other objects of the invention have to do with such features as means for maintaining positive control of the operating parts from the ground surface via the suspension means, and, more 20 specifically, a preferred plug structure according to which relatively vertically movable parts of the plug are caused to move relatively in opposite directions as the suspension means is rotated in opposite directions, and the valve, pipe engaging means and packer are actuated in accordance with and in response to movement of the said parts.

All the above mentioned features and objects of the invention, aswell as numerous additional '30 aspects unmentioned as yet, can perhaps be explained to best advantage and without necessity for further preliminary discussion by proceeding with a detailed description of a specinc form of plug that ^is illustrative ofthe invention in one of its typical and preferred forms. Throughout the description reference is had to the accompanying drawings, in which:

Fig. 1 is a general view showing the plug in -side elevation; 40

Fig, 2 is an enlarged sectional view taken 1ongitudinally through the plug and showing the valve open and the pipe engaging means and packer in radially contracted positions;

Figs. 3 and 4 are cross sections taken on lines 45 3;-3, and 4 4, Fig. 2; and

Figs, 5, 6 and 7 are half sections similar to Fig. 2, illustrating the sequential -movement of the plug parts beyond their positions in Fig. 2, during a complete plug setting operation. 5 The illustrated form of plug may be described generally as comprising a tubular body Ill-'connected by a swivel joint II-to asub |2,'which'in turn is connected by a right-handed screwthread joint I3 with the drill pipe I4 lon whichthe plug 55 is lowered within the casing I5. Extending within and below the body I6 isa tubular mandrel I6 movable vertically with relation to the body to cause expansion and'contraction of the pipe gripping means I1 and the packer I8. An inner tubular mandrel in the form of a pipe |9 operates by virtue of rotation of the sub I2 relative to the body I0 at the swivel to produce relative vertical movement of the body and mandrel I6, thereby controlling the operation of the pipe gripping means I1 and packer I8, and also to operate a valve 20 that controls the passage of well fluid longitudinally through the plug by way of bore 2|. The plug is held against rotation within the casing by suitable means, such as bowed springs 22, yieldably engaging the casing and, in effect, carried by the mandrel I6.

Body Ill comprises a tubular section 23 having at its upper end a counterbore 24 which receives the lower anged end I2a of the sub I2 and a threaded bushing 25. The sub is rotatable within the bushing and body, and its flanged portion |2a is vertically conned between the lower end 25a of the bushing and shoulder 26 at the lower end of counterbore 24. The body also may be regarded as including a supporting ring 28 threaded at 29 into the lower end of section 23. In the position of the parts shown in Fig. 2, ring 28 supports mandrel I6 and certain parts directly connected thereto, and also the pipe engaging means I1 and the packer I8,

In its preferred form, the pipe engaging means |1 comprises a plurality of wedge slips 30, typically four, each of which is connected to the ring 28 by a link 3| having bifurcated ends, as shown in Fig. 1, receiving a depending lug 3 2 on ring 28, and an upwardly projecting lug 33 on the slip. The link and lugs are interconnected by pins 34 and 35 extending through openings in the lugs with sucient looseness that a vertical end thrust on the ring, link and slip assembly, is taken by the engagement of the ends of the links with the surfaces of the ring and slips at opposite sides of the lugs, thus relieving the pins from stress. Slips 30 are contained within angularly extending ways 31 in a sleeve 38 movable vertically with relation to the mandrel I6. The slips are vertically movable within ways 31 along inclined wedge surfaces 39, and are radially conned within the ways by the slip flanges 40, see Fig. 4, extending within grooves 4| formed in the side walls of the ways in the bases thereof. One important advantage of mounting the slips on the body by links 3| is that the relative vertical positions of the slips remain the same, so that they expand and contract uniformly and thus evenly engage and disengage the pipe. l

Upward movement of the slips relative to the sleeve 38 is limited by their engagement with a ring 42 notched to receive the lower ends of links 3| and connected to the packersupporting ring 43 by bolts 44, see Fig. 1, extending through the sleeve and threaded at their lower ends into ring 43. The packer I8 comprises a rubber sleeve 44 attached by su'itable means to ring 43, as by looped wires or cables 45 embedded within the upper portion of the rubber. This type of flexible connection between the packer and lts supporting ring is of advantage in that it permits full expansion Vand exure of the packer and yet keeps it securely anchored to its support. The upper portion 46 of the packer bore has sliding engagement with the mandrel I6, whereas the lower portion 41 is ared outwardly to receive the mandrel carried expander, as will presently appear. At this point it may be noted that the assembly including ring 42, sleeve 38, ring 43 and the packer sleeve 44, is movable vertically with relation to the mandrel I6, and that upward relative movement of the assembly is limited by the engagement of ring 42 with the mandrel shoulder 48.

The mandrel I6 comprises a tube 49 on the upper end of which is threaded nut 50 which, in the positions of Figs. 2 and 5, seats on annular shoulder 5I within ring 28, to support the mandrel assembly on the body. The packer expander 52, consists of a conically shaped, upwardly tapering tubular member screw-threaded at 53 on the lower end of tube 49. In the illustrative form of the invention shown, a hollow nose member 54 is threaded at 55 into the lower end of the expander 52, although it is to be understood should it be desired to use the plug in combination with any form of tool, such as a bit, the nose member 54 may be replaced by a suitable sub or coupling for -connecting the mandrel with such tool. The plug is readily adaptable for use in conjunction with the tool carried below, in that, as will later appear more fully, fluid circulation may be maintained through the plug to the tool during such times as the latter may be in operation.

As shown in Fig. 1, openings 56 are provided in the lower end of the plug nose 54 to permit passage of well fluid through the plug by way of the inner pipe bore 2|. The mandrel is held against rotation within the casing by means of spring bows 22 welded at 51 to the nose 54, the

upper ends of the springs being received within and slidably engaging the bases of grooves 56 in the expander 52. The valve mechanism 20 at the lower end of the expander comprises the valve proper, denoted at 59, having a tubular guide extension 59a contained within counterbore 60.

Ports 6I pass the fluid between space 62 and passage 2| when the valve is open. The valve' is yieldably urged toward closed position in which it seats at 63 on the lower end of expander 52, by a coil spring 64 placed about tube 66 and supported on an apertured plate or spider 65.

Pipe I9 moves vertically within the mandrel to operate the valve 59, the pipe in its lower position of Fig. 2 engaging the guide 59a and depressing the valve against the resistance of spring 64 to hold the valve in open position. Relative rotation between pipe I9 and the mandrel is prevented by spline 68 carried by the pipe and received within a vertically extending way 69 in the expander bore. Pipe I9 is vertically movable relative to the mandrel within the limits of engagement of thepipe flange 10 with nut 50 and shoulder 1| at the lower end of counterbore 12 in the upper end of tube 49. The distance of travel permitted pipe I9 as limited by the engagement of flange 10 with nut 58 and shoulder 1|, is somewhat) greater than the distance through which valve 59 moves in closing from the full open position of Fig. 2. This distance also is suilcient l to prevent accidental reopening of the valve in the plug setting operations and to permit movement of the mandrel under the influence of the well pressure to expand the packer, but without injury to the pipe gripping parts as will presently appear. Above nut 56, pipe I9 carries a guide member 13 of circular cross section slidably engaging the bore 14 of body section 23, and provided with circularly spaced passages 15.l Guide 13 is held against rotation about pipe I9 by spline 16, and is clamped between shoulder 11 and a lock washer 18 seated within a groove within the surface of the pipe. The guide is slidable vertically Within bore 14, but is prevented from rotating within the body by spline I9 received :,vithin a vertically extending way 80 in the body ore.

The upper end portion of pipe I9 has a screwthreaded connection at 8l with the sub I2, the

screw threads 82 being left-handed so that as=the sub is rotated in a counter-clockwise direction, the pipe is elevated relative to the body I8, through\the successive positions shown in Figs. 5, 6, and 7.. The lower end of the sub is provided with vertically extending passages 83 through which circulating fluid may be forced downwardly into boreI 14, passages 'I5 and thence outwardly into the well around links 3 I, as will later appear.

In operation, the plug, with its parts positioned as in Fig. 2, is lowered within the casing I5 on the drill pipe I4 to the location at which the plug is to be set. 'I'he right-handed screw-thread joint at I3 between the drill pipe and. sub I2 first will have been taken up snugly but not so tight as to prevent the joint from being unsorewed after the plug has been set. While the plug is being lowered within the casing, the valve 59 is held open, permitting the well fluid to pass upwardly through the plug into the drill pipe and thereby balancing the hydrostatic columns inside and outside the drill pipe. With the plug lowered to proper position, the drill pipe I4 and sub I2 are rotated in a counter-clockwise direction, first causing pipe I9 to be raised to the position of Fig. 5 in which the lower end of the pipe is disengaged from the valve, permitting it to seat. Fig. 5 also shows flange 'I0 to be raised to the point of engagement with the mandrel Inut 50. Continued rotation of the drill pipe causes pipe I9 to elevate the mandrel, together with sleeve 38 and packer 44, -to the position of Fig. 6 inAwhich the wedge slips 30 are shown to be expanded into engagement with the casing I5. It will be understood that sleeve 38 is supported in its upward slip expanding movement by packer 44, which in turn is supportedon the expander 52, and that the packer sleeve has suicient strength or resistance to distortion, by reason of its resilience, to support sleeve 38 in its slip expanding movement.

With the slips thus set, holding sleeve 38 against further upward movement, continued rotation of the drill pipe causes pipe I9 to raise the mandrel to the position of Fig. '7, in which the expander 52 is thrust upwardly into the packer bore a distance sutlicient to expand the packer, by virtue of the wedging engagement between the packer surface 41 and the tapered expander surfac' 52a, into iiuid-tight engagement with the casing. The plug now is fully set, and, may be disconnected from the drill string by continuing the left-hand rotation to break the joint at I3, the combined force of springs 22, packer I8 and the pipe engaging means I1, acting to hold the plug against rotation within the casing. Before the plug is disconnected, iiuid circulation into the casing above the packer may be effected by forc- Aing the fluid downwardly through passages 83, l5,

space 86 between tube 49 and ring 28, and outwardly between rings 28 and 42 and around the links 3|.

Obviously, the plug may be released while the drill pipe remains connected to the sub I2, or, otherwise, by again lowering the drill pipe and by -right-hand rotation making the joint at I3. Continued right-hand rotation first moves pipe tor. All that is required to be done by the oper- 3 I9 downward to the point of engaging the valve guide 59a and unseating the valvel 59, thus opening passage 2I for the relief of well pressure below the plug, so that the pressures above and belowY the packer 44 will be equalized. Further righthanded rotation of the drill pipebrings ange 'III into engagement with the mandrel shoulder 'II and withdraws the expander 52 from the packer to the extent that the packer assumes its normal contracted form. Further downward movement of pipe I9 brings the mandrel shoulder, 48 into engagement with ring 42, forcing sleeve 38 downward to slip releasing position, in which all the parts will have returned to the position shown in Fig. 2. J l5 It is to be noted that all the described sequences involving the operation of the'valve, pipe engaging means and packer, are predetermined andinsured against any variation by the operaator is to rotate the drill pipe in one direction or the other as required for setting or releasing l the plug. The automatic characteristics of the tool predetermine the operating sequence of its parts. No injury can occur to the plug by reason of excessive rotation of the drill pipe in one direction or the other, since in the setting operation, the joint at I3 will unscrew when the plug parts are properly positioned, Whilegin the releasing operatipn, rotation beyond the point of releasing the packer and slips will merely rotate the plug freely within the casing.

Another important feature of the invention that lends indestructibility to the plug,l and particularly to the parts directly associated with the pipe engaging means, is the fact that after the wedge slips are set against the casing and the packer is expanded, excessive well pressure tending to force the plug upwardly within the casing, will not impose strains on the slip actuating parts. After the slips are set, increased well pressure acting against the mandrel will merely expand the packer more tightly into engagement with the casing and cause the mandrel to move upward within sleeve 38 withoutaffecting either the sleeve or the slips.

It will be understood thatI in the claims, such terms as upward, downward, 1owered, vertical, and vertically are to be regarded as relative only; that is, these terms are employed merely for convenience of terminology in defining 'direction or position with relation to a vertically extending well pipe.

I claim:

1. In ai plug adapted to be lowered within a Well pipe on a suspension means, the combination comprising a body, means connecting said body with the suspension means and adapted to allow relative movement therebetween, a valve normally held open while the plug is being lowered to permit fluid to pass upwardly through said body, means for holding the valve open, pipe engaging means adapted to be radially expanded into engageme'nt with said `pipe to hold the body against upward movement therein, a packer adapted to be radially expanded into iiuid tight engagement with the pipe, control mechanism operable by y movement of the suspension means in one direction with respect to the body to close said valve and to radially expand said pipe engaging means and packer into engagement with the pipe, said mechanism also being operable by movement of the suspension means in an' opposite direction with respect to the body to open the valve and toA radially contract the pipe engaging means and packer, and yielding means carried by the plugand engaging the Well pipe, said yielding means holding said body against movement relative to the well pipe during operation of said control 5 mechanism 2. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a body, means connecting said body with the suspension means and adapted to allow relative rotation therebetween, a valve normally held open while the plug is being lowered to permit iuid to pass upwardly through said body, ,means for holding the valve open, pipe engaging means adapted to be radially expanded into engagement with ysaid pipe to hold the body against upward movement therein, a packer adapted to, be radially expanded into uid tight engagement with the pipe, control mechanism operable by rotation of the suspension means in one direction with respect to the body to close said valve and to radially expand said pipe engaging means 'and packer into engagement with the pipe, said mechanism also being operable by rotation of the Suspension means in an opposite direction with 26 respect to the body to open the valve and to radially contract the pipe engaging means and packer, and yielding means carried by the plug and engaging the well pipe, said yielding means holding said body against rotation relative to the i well pipe during operation of said control mechanism.

3. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a body, means connecting the plug with said suspension means, yielding means carried by said plug and engaging the pipe, a valve controlling the iiow of fluid through a passage extending through the plug, radially expansible pipe engaging means, a radially expan- 40 sible packer, control mechanism actuated by the suspension means whereby repeated rotation of the suspension means in opposite directions while the plug remains in the pipe', causes said valve to repeatedly close and open and said expansible pipe engaging means and packer to repeatedly expand and contract, said yielding means engaging the well pipe to hold said body against movement -relative to the well pipe during the said operations of the valve, expansible pipe engaging means and packer.

rality of radially expansible wedge slips, links having their opposite ends prvotally connected to said body and slips so that the slips are movable with the body in its vertical movement relative to the mandrel, an annular slip actuating wedge ring slidable longitudinally on the mandrel,

a radially expansible vpacker mounted on the mandrel and connected to said ring, and upwardly movable packer expanding means carried by the mandrel, said slips and packer being ex` pansible by upward movement of the mandrel within the body.

5. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a tubular body, a mandrel within the body and movable vertically relative thereto, radially expansible :pipe engaging members, a plurality of links connecting the lower end of said body with said pipe engaging members, a wedge ring movable vertically on the mandrel and operable upon upward movement of the mandrel within the body to radially expand the pipe engaging means, a packer connected to the wedge ring, and upwardly movable means for radially expanding the packer by upward movement of the mandrel relative to the body, said packer, when acted upon by said last mentioned means, acting on said wedge ring so to operate it.

6. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a tubular body, a mandrel within the body and movable vertically relative thereto, radially expansible pipe engaging members, means connecting the lower end of said body with said pipe engaging members, wedge means movable vertically on the mandrel and operable upon upward movement of the mandrel within the body to radially expand the pipe engaging means, a packer surrounding the mandrel below said upwardly movable wedge means and connected thereto, and Wedge means for radially expanding the packer by upward movement of the mandrel relative to the body.

7. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a tubular body, a mandrel within the body and movable vertically relative thereto, radially expansible pipe engaging members, means connecting the lower end of said body with said pipe engaging members, a wedge ring surrounding the mandrel and movable vertically relative thereto, said ring being operable to expand said pipe engaging members upon upward movement relative thereto, a packer below said wedge ring and connected thereto, and an annular upwardly movable packer expanding wedge carried by the mandrel within the packer, said packer and pipe engaging members being radially expansible by upward movement of the mandrel within the body.

8. In combination, a plug adapted to be lowered within a well pipe on a suspension means, said plug including a body, a swivel joint between the body and suspension means whereby said body and suspension means are capable of relative rotation, pipe engaging means adapted to 'be radially expanded into engagement with said pipe to hold the body against upward movement therein, a packer adapted to be radially expanded into fluid tight engagement with the pipe, a e

valve adapted to be open while the plug is being moved longitudinally through the pipe to permit well-iiuid to by-pass the packer, releasable means for holding the valve open, and control mechanism operable by rotation of the suspension means with respect to the body member at said swivel joint first to close said valve and then, after the valve is closed, to expand said pipe engaging means and packer into engagement with said pipe.

9. In a plug adapted to be lowered within a well pipe ony a suspension means, the combination comprising a body, means connecting said body with the suspension means and adapted to allow relative movement therebetween, a valve normally held open while the plug is being lowered to permit fluid to pass lupwardly through said body, means for holding the valve open, pipe engaging means adapted to be radially expanded into engagement with said pipe to hold the body against upward movement therein, a packer adapted to be radially expanded into uid tight engagement with the pipe, control mechanism operable by movement of the suspension means in one direction with respect to means exclusively in an opposite direction with respect to the body to open the valve and to radially contract the pipe engaging means and packer, and yielding means carried by the plug and engaging the well pipe, said yielding means holding said body against movement relative to the well pipe during operation of said control mechanism.

10. In a plug adapted to be lowered within a well pipe on/a suspension means, the combination comprising relatively vertically movable 'body and mandrel sections, radially expansible pipe engaging means. supported by and suspended from the body section, an annular packer normally suspended from the vpipe engaging means, said pipe engaging means and packer both being movable vertically with the body section in its said relative vertical movement, and means wherebyrelative movement of the sections in one direction causes the pipe engaging means and packer to radially expand, and whereby relative/movement of the sections in an opposite direction causes the pipe engaging means and packer tol contract.

11. In a plug adapted to be lowered within a well pipe on a suspension means, the combination comprising a body, means connecting said body with the suspension means -and adapted to allow relative rotation therebetween, said connection including a joint breakagle by selective y relative rotation of its parts upon the imposition of pre-determined torque, a valve normally held open while the plug is being lowered to permit uid to pass upwardly through said body, means for holding the valve open, pipe engaging means adapted to be radially expanded into engagement with said pipe to hold the body against upward movement therein, a packer adapted t'o be radially expanded intouid tight engagement with the pipe, control mechanism operable by sustained rotation of the suspension means in one direction with respect to the body to close said valve, radially expand the pipe engaging means and packer into engagement with the pipe and break said joint to free the suspension means from the plug; and yielding means carried by the plug and engaging the well pipe and thereby holding said body against rotationv with respect to the pipe during operation of said control means prior to the effective engagement of the rst mentioned pipe engaging means with the well pipe.

12. In combination, a plug adapted to be lowered within a well pipe on suspension means.

- ported by the body and mounted for vertical movement with respect thereto, an upwardly facing packer expandernear the lower end of the sleeve, an annular packer supported in coaxial relation to the sleeve and positioned above the expander, a tubular, upwardly pointing wedge member slidably mounted on the sleeve above the packer expander, expansible wedge slips suspended from the body and cooperatively engaging the wedge member, an operating mandrel mounted within the sleeve bore and adapted, during upward movement thereof, to move the sleeve and the packer-expandingmember vertically with respect to the body, means holding the mandrel, body member and sleeve against relative rotation, casing-engaging means connected to said sleeve, a swivel joint between the suspension means and the body near its upper end, and a screw-thread connection between said operating mandrel and the body at a point, in eiect, above said swivel joint.

13. In combination, a plug adapted to be lowered within a well pipe on suspension means, said plug including a tubular body, a sleeve supported by the body and mounted for vertical movement with respect thereto, an upwardly facing packer expander near the lower end of the sleeve, an annular packer supported in coaxial relation to the sleeve and positioned above the expander, said plug having a passage adapted to by-pass well iiuid around the packer, a springpressed valve for controlling said passage and carried by said sleeve, a tubular, upwardly pointing wedge member slidably mounted on the sleeve above the packer expander, expansible wedge slips suspended from the body and cooperatively engaging .the wedge member, an operating mandrel non-rotatably mounted within the sleeve bore and capable of limited vertical movement with relation to the sleeve, said mandrel, in one of its positions of vertical adjustment with respect .to the sleeve, engaging the valve to hold it open, said mandrel freeing the valve for opening movement when the mandrel is moved upwardly from that position, and nhoulders on the sleeve and mandrel engaging one another upon continuation of such upward movement to move the sleeve and the packer-expanding member vertically with respect to the body, means holding the mandrel, body member and sleeve against relative rotation, casing-engaging means connected to said sleeve, a swivel joint between the suspension means and the body near its upper end, and a screw-thread connection between said operating mandrel and .the body at a point, in effect, above said swivel joint.

' S. KNOX.

CERTIFICATE 0E CORRECTION. Patent No. 2,205,7u. June 25, 191m.

CRANVILIE fs. KNOX.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l1., second x column, line 20, claim 6, strike out the words "upwardly movable" and insert the same before wedgel in line 21, same claim; page 5, first column, line 51+, claim l1, for "breakagle" read'-br`eakable; and second column, line 11.6, claim 15,for "nhoulders" read --shou1ders; and that the said Let-ters Patent should be read with this correction therein that the same" may conform to the record of the case in the Patent Office.

signed and Sealed this auth day of september, A. D. 191m.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents. 

